With the rapid development of portable and wearable electronics, energy storage devices featuring high energy and power densities, long-cycle lifetime, environment friendliness, safe operation, lightweight, ultrathin thickness and flexibilityl have become increasingly important. Herein, a high-performance flexible quasi-solid-state Ni–Fe battery was rationally developed by engineering the surfaces of α-Fe₂O₃ nanorods (NRs) and NiCo₂O₄ nanowire arrays (NWAs) as the anode and cathode, respectively. Benefiting from the flexible current collector, fast charge transport, rapid ion diffusion, and sufficient electroactive sites, this flexible quasi-solid-state Ni–Fe battery presents outstanding capacity as high as 134.5 mA h g⁻¹. Furthermore, this battery also has long cycling life, and could be cycled up to 2600 times with 82.7% capacity retention. Most importantly, the as-fabricated flexible quasi-solid-state Ni–Fe battery achieves an admirable energy density of 227 W h kg⁻¹, together with a peak power density of 23.4 kW kg⁻¹, thus outperforming the most recently reported Ni–Fe batteries and other flexible energy storage devices. Coupled with the advantages of admirable energy density and durability, this highly flexible and rechargeable Ni–Fe battery will greatly enrich the energy storage technologies for future flexible electronic device applications.

中文翻译：

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基于表面工程的柔性可充电准固态镍铁电池表现出高能量和长寿命†

随着便携式和可穿戴电子设备的迅速发展，具有高能量和功率密度，长寿命，环境友好，安全操作，轻便，超薄厚度和柔性的储能装置变得越来越重要。在本文中，一个高性能柔性准固态镍-铁电池，合理地通过工程化的α-Fe的表面开发_2个ö ₃纳米棒（NRS）和镍钴₂ ö ₄纳米线阵列（NWAS）作为阳极和阴极，分别。得益于灵活的集电器，快速的电荷传输，快速的离子扩散和足够的电活性位点，这种灵活的准固态镍铁电池具有出色的容量，高达134.5 mA汞柱^-1。此外，该电池还具有较长的循环寿命，可以循环使用2600次，容量保持率为82.7％。最重要的是，制成的柔性准固态Ni-Fe电池可实现227 W h kg ^-1的令人赞叹的能量密度，以及23.4 kW kg ^-1的峰值功率密度，从而胜过最新报道的Ni –Fe电池和其他柔性储能设备。加上具有令人赞叹的能量密度和耐用性的优点，这种高度灵活且可充电的镍铁电池将极大地丰富储能技术，以适应未来的柔性电子设备应用。